「是…的」（强调） "shì … de"
「是…的」（强调）（"shì … de"）means “是…的: emphasize the time / place / manner of a past action”. For an action already known to have happened, the 是…的 frame highlights a detail — WHEN, WHERE, or HOW it happened: 我是坐飞机来的 'It was by plane that I came'. Formation: 是 + 强调部分（时间/地点/方式）+ 的（针对已发生的动作）
是…的: emphasize the time / place / manner of a past action
HSK2Formation
是 + 强调部分（时间/地点/方式）+ 的（针对已发生的动作）
Explanation
For an action already known to have happened, the 是…的 frame highlights a detail — WHEN, WHERE, or HOW it happened: 我是坐飞机来的 'It was by plane that I came'. 是 goes before the emphasized part, 的 at the end. 是 can sometimes be dropped, but 的 stays.
Examples
Note
For already-happened actions; 的 read neutral 'de'.
FAQ
「是…的」（强调） — what does it mean and how is it used?
是…的: emphasize the time / place / manner of a past action. For an action already known to have happened, the 是…的 frame highlights a detail — WHEN, WHERE, or HOW it happened: 我是坐飞机来的 'It was by plane that I came'. 是 goes before the emphasized part, 的 at the end. 是 can sometimes be dropped, but 的 stays.
「是…的」（强调） — how do you form it?
是 + 强调部分（时间/地点/方式）+ 的（针对已发生的动作）
「是…的」（强调） — any usage notes?
For already-happened actions; 的 read neutral 'de'.